Introduction

Abstract

Channeling is the process where charged particles are steered by the rows or planes of atoms in a perfect crystal. This can occur when a particle beam is aligned with major crystal axes or planes or when particles are created in a crystal. Related processes include coherent bremsstrahlung and coherent pair production from aligned high-energy photon beams. Channeling has contributed in important ways to our understanding of particle motion in solids at the fundamental level and, just as significantly, has led to numerous applications in physics and technology. Furthermore, it presents a new source of interesting and challenging mathematical problems in dynamical systems and stochastic processes. Much of the early work focused on MeV energies and heavy particles; however, during the last decade there has been an increasing realization that the interaction of relativistic particles with aligned single crystals is interesting.